Biodiversity of the Ingoda River ecosystem

The results of a study of the biodiversity of hydrobionts in the Ingoda River are presented. In phytoplankton sixty six taxa of algae with a rank below the genus have been identified. The zooplankton contains 21 species. The species composition of the macrophytobenthos includes 5 taxa. In the flora of hydrophytes, 15 plant species have been identified. The zoobenthos contains 40 species. Our researches have been showed that widespread species prevail in the flora and fauna of hydrobionts in the Ingoda River. Two alien species (Elodea canadensis and Gmelinoides fasciatus) have been recorded in the Kenon Lake. A very rare East Siberian species of mayfly Acanthametropus nikolskyi has been recorded in the Ingoda River zoobenthos.

Study of Elodea canadensis elimination of Sodium Dodecyl Sulphate and NH4Cl

The absorption of an anionic surfactant - sodium dodecyl sulfate (SDS) by a Elodea canadensis was studied. Macrophyte (20 g/L wet weight) reduced the concentration of this surfactant from 2 mg/L by 90% within 2 days. A negative effect of SDS on the elimination of ammonium nitrogen by E. canadensis was shown with its content from 1·10-4 M. Thus, in the presence of 1·10-4 M SDS, E. canadensis reduced the concentration of ammonium nitrogen by 51% of the initial value in 2 days (in the control - without surfactants - 92% of the pollutant was absorbed).

Efficacy of florpyrauxifen-benzyl for eurasian watermilfoil control and nontarget Illinois pondweed, elodea, and coontail response

This research evaluated low concentrations and short exposure times of the recently registered aquatic herbicide florpyrauxifen-benzyl (4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)-5-fluoro-pyridine-2-benzyl ester) on the target plant Eurasian watermilfoil (Myriophyllum spicatum L., hereafter referred to as EWM) as well as selectivity towards the nontarget submersed species Illinois pondweed (Potamogeton illinoensis Morong), elodea (Elodea canadensis Michx.), and coontail (Ceratophyllum demersum L.)

Diversity of Macrophytes and Environmental Assessment of the Ljubljanica River (Slovenia)

The present research aimed to determine the diversity of macrophyte taxa in the Ljubljanica River and its relationship with environmental parameters. In each of the 19 river sections, the presence and abundance of plant taxa were recorded, and basic physical and chemical parameters were measured. Additionally, selected environmental parameters were assessed using a modified version of the Riparian, Channel and Environmental (RCE) method. We compared the obtained data set with survey data from the year 2004. In 2019, a total of 34 macrophyte taxa were recorded. The dominant taxa with the highest abundance were Sparganium emersum, Callitriche sp., and the invasive alien species Elodea canadensis. The species richness and diversity of macrophytes decreased with distance from the source, an increase in pH, and alterations of the riverbed structure due to interference in the riverine ecosystem in the lower part of the Ljubljanica River and its catchment. The comparison of 2004 and 2019 surveys revealed a decrease in the overall presence and abundance of P. natans and in the frequency of occurrence of the species Myriophyllum spicatum and an increase in the presence and abundance of the invasive alien species Elodea canadensis.

The adaptive capabilities of Elodea canadensis under the influence of anthropogenic factors

Studies on the potential adaptation of one of the common aquatic macrophytes Elodea canadensis when immersed in a medium containing anthropogenic pollutants of various origins – metals (inorganic salts); organic salts, mineral acids; oil and its derivatives - water-soluble petrochemicals. It was found that almost all the studied pollutants do not show a clear external effect on the solid fragments of the plant (cell membranes). Thus, it was shown that Elodea canadensis is tolerant of anthropogenic pollutants that differ in nature, hazard class, physico-chemical properties, etc.

Elodea canadensis (Canadian pondweed).

Elodea canadensis is a submerged aquatic plant of slower flowing rivers, native to North America. It has been intentionally introduced into areas outside of its native range as an ornamental aquarium species. This species has a wide ecological tolerance and grows relatively fast. It is a perennial, overwintering in the deeper water, and reproducing asexually. Disturbance increases the dispersal of numerous propagules and the vigorous re-growth is enhanced through changes in availability of nutrients. E. canadensis can form dense mats which can interfere with recreational activities, navigation and port infrastructure. In addition to this, the dense mats outcompete native plant species and therefore decrease the biodiversity in an area. It also accentuates the accumulation of finer organic silts which enhances its growth further as nutrients are released. E. canadensis is considered invasive in Australia, New Zealand, Cuba, Alaska and the majority of European countries where it is present. Control is complicated and loss of fragments should be minimized to prevent further spread. It is included in the IUCN Red List, categorized as being of Least Concern. Thus, no conservation action is proposed or is necessary for this species.